Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
Results
Showing 1 to 13 of 13 for “"chemical cleaning"”.
-
The effects of commercial chemical cleaning processes on sandstones in Scotland.
… programme investigated the effects of commercial chemical cleaning processes on sandstones in Scotland. The work follows a logical path from an understanding of the materials, both the stones and the chemical cleaners, involved. There is a great variation in sandstone types commonly used in …
-
Mechanisms of MS2 bacteriophage removal by ultrafiltration membrane with different foulants
… from membrane bio-reactor (MBR) feed water, and cleaning methods including backwashing and chemical cleaning. The membrane conditions tested were pristine membrane, membrane fouled by SMP, backwashed membrane, and chemically cleaned membrane. The order of MS2 removal by these membranes was: …
-
Development of chemical-free methods of fouling mitigation for membrane processes in desalination
… performance, desalination plants resort to chemical cleaning, incurring losses in productivity, chemical cost, and membrane replacement all while raising environmental concerns associated with chemical waste. In this work, we explore alternative chemical-free methods of membrane fouling …
-
Investigation of Membrane Fouling and Cleaning in Direct Contact Membrane Distillation of Municipal Wastewater
… potable reuse. This project investigated the chemical cleaning efficiency of ethylenediaminetetraacetic acid (EDTA) on membrane wastewater effluent fouling for direct contact membrane distillation (DCMD) to help assist wastewater reuse become a reality. A laboratory scale DCMD system was …
-
Causes and analysis of failures in in-situ microscopy observation for the characterization of scaling in membrane distillation membranes
… potentially costly procedures like intense chemical cleaning or membrane replacement are necessary. Some theory suggests that, instead of reacting and adhering to membrane surfaces, salts tend to bulk nucleate in solution, and then deposit on high energy surfaces, like metal heat exchangers …
-
Deformation-assisted antifouling of surfaces
… to ice formation on the wings of planes Chemical cleaning of the surfaces is often seen as the de facto treatment, but the drawbacks include the costs of using chemicals, environmental impact and long duration required for the reaction of the chemicals with the foulant With the increased …
-
Factors influencing salt-induced weathering of building sandstone.
The role of chemical cleaning in causing salt-induced weathering of building sandstone was investigated by looking at the changes in a series of weathering indicators selected. These were mainly, porosity and pore size distribution changes, chemical composition and colour changes. Laboratory …
-
Development of Aerobic Granular Sludge Membrane Bioreactor (AGMBR) to Mitigate Fouling
… times reduction in permeability maintenance cleaning frequency of the membrane. The COD showed a significant main effect on both PN and PS components of TB-EPS at α < 0.05. Water jet easily sloughed off the developed membrane cake layer, eliminating the need for chemical cleaning. The AGMBR …
-
Studies of modified pumice and titanomagnetite filtration media
… less reliance on the use of water treatment chemicals. In order to develop new options for granular filtration systems, two indigenous New Zealand media, titanomagnetite (TM) and pumice were investigated. TM was of interest because its particle size is finer than most filtration media and its …
-
Membrane Fouling Mitigation with Water Hammer
… in membrane performance and requires regular chemical cleaning to sustain the operation. This thesis focuses on the development of a new approach to mitigate fouling by subjecting a membrane to water hammer. The water hammer was generated by a solenoid valve installed at the retentate side of …
-
The effects of ion bombardment on the chemical reactivity of GaAs(100)
The effects of ion bombardment on the chemical reactivity of GaAs(100) were investigated by X-ray photoelectron spectroscopy. The enhancement in reactivity was shown to be related to the energy and mass of the bombarding ion. The oxidation results were compared to chemically cleaned (1:1 …
-
Remediation of spent oxalic acid nuclear decontamination solutions using ozone
… waste generated primarily from cold-war radiochemical separations. All of the tanks eventually must be closed. As part of decommissioning/closing the nuclear waste tanks, even residual quantities of the waste must be removed. Although most sludge can be removed mechanically, chemically …
-
Control of size and charge selectivity in amphiphilic graft copolymer nanofiltration membranes
… to acid (pH 2) solution, used to simulate chemical cleaning procedures in industry. Thickness-normalized permeabilities of these PAN-g-PEOn NF membranes exceeded those of commercially available NF membranes by approximately an order of magnitude. A systematic effect of side chain length on …